1. Field of the Invention
The present invention relates to a satellite receiver to receive the radio wave from the satellite and, more particularly, to a satellite receiver which inhibits the reception of the program which should not be seen by children.
2. Related Background Art
The satellite receiver adapted to receive the radio wave from the satellite directs the parabola antenna toward designated one of several satellites placed in a geostationary orbit in the equatorial space and then receives the radio wave which is generated from the designated satellite by the parabola antenna. The received signal is transmitted through the feed horn to switch the horizontally polarized wave and vertically polarized wave to the low noise amplifier and amplified. The amplified output of the low noise amplifier is converted to the frequency of, e.g., 1 GHz by the block down converter and supplied to the receiver including an image receiver and received. On the other hand, the satellite is provided with the transponders of, for example, twenty-four channels at intervals of 40 MHz. The antenna controller receives the output from the receiver and supplies a drive output to the parabola antenna and rotates the parabola antenna in the directions of east and west in response to the output from the receiver, thereby directing the antenna toward the designated satellite. In this manner, the antenna controller can select the proper satellite.
However, all of the programs from the satellites are not always suitable for children to see. There are also some programs which, the parents consider, should not be seen by the children. There is the case where the parents want to prevent the radio waves of such programs from being received by the children. Such an inhibition of reception will be referred to as a lock or parental lock in this specification.
In the conventional satellite receiver, the receiver itself is locked. Therefore, when the receiver is locked, all of the functions of the receiver cannot be operated, so that there is a drawback such that no radio wave can be received.